Absorbent products intended to absorb discharged body fluids are well known in the art. Such absorbent products generally comprise a fibrous mass or other absorbent body which can absorb and hold body fluids. The absorbent articles have included various systems of liquid-handling layers, such as intake layers, distribution layers, retention layers and the like. Additionally, the absorbent articles have included patterns of embossments distributed on the bodyside surface of the article to provide a hinging action, or to inhibit or direct a desired flow of liquids. Usually, in a given package of absorbent articles, every absorbent personal care article in the package has essentially the same embossing pattern.
Typically, the absorbent articles are placed in purses, backpacks, briefcases, and the like which do not always provide a hygienic environment for the articles, and thus the articles can become dirty and/or damaged. Further, the articles can become scattered about in purses, backpacks, briefcases, and the like so they are difficult to find when needed. Thus, in order to avoid these problems, personal care products are individually wrapped or are wrapped in groups of 2-5 absorbent articles in a pouch or similar wrapper. Typically, such wrappers have a solid colour, or have a pattern that covers the entirety of the wrapper and each wrapper within the packaging component is identical to each other.
Selecting a particular design for the personal care articles as well as the wrappers can be a deciding factor. While being liked by some consumers, other consumers may dislike the design. Those consumers who dislike the design may be more likely to complain about the product, or stop purchasing the product based on their dislike of the design.
In the case of feminine care products, such as sanitary napkins, incontinence pads, panty liners and the like, there is a need for an absorbent article which can provide a possible emotional benefit to the user. Many females experience a down turn in their mood during the menstrual period. Generally, sanitary napkins have a white colour or a simple combination of colours to provide a sanitary appearance. Within a given package of sanitary napkins, each sanitary napkin will look essentially identical to the other sanitary napkins in the package. As a result, the user of the sanitary napkins is provided with essentially no emotional benefit by the appearance of the sanitary napkin. Therefore, there is a need in the art to provide a possible emotional benefit to the users of the feminine care products.
In the case of diapers and incontinence protectors, the exterior of these disposable absorbent articles is covered with a flexible, liquid impervious member to prevent a leakage of absorbed liquids from the disposable absorbent articles. Such a liquid impervious member is generally referred to as a backsheet, and is often constructed from a liquid impervious material such as a polyethylene film, and, if desired, other outer cover material such as a nonwoven material. The backsheet constitutes the garment contacting surface of the absorbent articles.
It is also known that the garment contacting surface of the absorbent articles often has printed graphics to get a positive attention from the user or caregiver not only in use but also in the market. In the latter case, the absorbent articles are often contained in a package having a transparent portion such that the graphics are visible through the transparent portion. Such graphics are typically printed on either a landing zone material or a backsheet material. Graphics printed on the garment contacting surface of disposable absorbent articles can be preferred by consumers due to their entertaining functions.
Those graphics are typically printed by using conventional printing techniques such as gravure and flexography technologies which employ a printing plate to print the graphic on a sheet material, e.g. a backsheet material, a landing zone material, or a fastening tape material. The printing plate has ink images for graphics to be printed. The printing plate is typically mounted on a printing cylinder in a printing process. In the printing process, when the cylinder rotates, the printing plate transfer the ink images to the sheet material by contacting the sheet material thereby printing the graphics thereon.
The number of the ink images which can be prepared using a given cylinder depends on the sizes of the ink images in relation to the size of the cylinder. In general, since the size of the landing zone member is not large, the size of the ink images prepared in the printing plate tends to be small. On the other hand, since the size of the backsheet is relatively large, the size of the repeated ink images tends to be large. The number of the graphics to be printed is thus limited in particular for a relatively large component material of disposable absorbent articles such as a backsheet material. Because of the above reasons, the variety of the graphics printed on conventional disposable absorbent articles is limited in one package.
Thus, it is understood that this limitation results in preventing users or consumers from enjoying more variety of graphics in the disposable absorbent articles packed or contained in one package.
Several attempts have been made in order to overcome such a limitation, and to provide a method for printing or embossing a large number of different graphics.
WO 2006/068673 suggests a package wherein every absorbent article and/or a wrapper component may have a different pattern embossed or printed on the body facing surface or the garment facing surface of each of the absorbent articles.
According to WO 2006/068673, the different embossing patterns on the absorbent personal care articles or the wrapper components may be imparted in many different ways, including using side-by-side production lines, a single production line with separate embossing sections, i.e. a single line splitting into two or more lines to emboss the absorbent personal care articles or the wrapper components, using a single process line and preparing the absorbent personal care articles or the wrapper components in a batch process, changing the embossing roll after each batch of absorbent personal care articles or the wrapper components, or a single production line and using an embossing roll with a long repeat pattern. By a long repeat pattern, it is meant that several absorbent personal care articles or the wrapper components are embossed before the pattern repeats itself. This can be accomplished by using, for example, a large diameter embossing roll. Other types of embossing rolls, such as embossing rolls with several different patterns across the width of the roll may also be used.
WO 2010/042470 suggests a process and apparatus for printing a series of different graphics on substrates used in the manufacture of absorbent articles. Embodiments of the apparatuses and methods disclosed in WO 2010/042470 utilize flexographic printing to provide for a sequential manufacture of a series of n absorbent articles having different graphics printed thereon, wherein n can be a number of 2 or greater. In addition, an absorbent product may be produced by placing one or more, or a portion, of the series of n absorbent articles in a package.
An apparatus of WO 2010/042470 for printing disposable absorbent articles includes: a central impression cylinder defining an outer circumferential surface; and a plurality of printing stations positioned adjacent the outer circumferential surface of the central impression cylinder. Each printing station includes: a printing roller; an endless belt having a first surface and a second surface opposite the first surface, wherein the second surface partially surrounds the printing roller and wherein the printing roller is adjacent the central impression cylinder so as to define a nip between the first surface of the endless belt and outer circumferential surface of the central impression cylinder; a first plurality of n printing patterns operably disposed on the first surface of the endless belt, wherein n is 2 or greater; an ink supply; and an anilox roller operably connected with the ink supply and the endless belt wherein the anilox roller is adapted to deposit ink from the ink supply onto the first plurality of n printing plates.
EP 1 884 360 discloses a printing unit comprising a plurality of plate rollers disposed in series along a path of the web material, so that said web material is decorated with a print obtained by the combination of designs printed by said plate rollers, wherein at least some of said plate rollers have printing plates with printing extensions of different lengths from one another, equal to multiples of the longitudinal dimension of the sheets into which the web material is divided and each of the plates has a plurality of motifs of a length equal to said longitudinal dimension. Moreover, on each printing plate there is provided at least one series of designs different from one another and the designs of the plates of said at least two rollers differ from one another at least in part.
WO 2004/064872 describes a method of printing a graphic on a component material for absorbent articles. The graphic data is stored in a graphic memory for printing n graphics, n being greater than 2; and then selected and printed by an ink jet on the sheet material. The process is repeated so that the n graphics are printed on the sheet material.
WO 2004/064872 also discloses a method of producing an absorbent product including a package and at least n absorbent articles contained in the package, wherein n is greater than 10. The method includes the steps of: (a) supplying a sheet material having a plurality of printing frames sequentially disposed along the machine direction, wherein each printing frame includes n graphics printed sequentially in the machine direction; (b) incorporating other component materials with the sheet material to form n absorbent articles in the machine direction, wherein each absorbent article have a corresponding graphic of the n graphics; (c) detecting the printing frame in the sheet material; (d) transporting the absorbent articles which are within the detected printing frame; and (e) packing the transported absorbent articles into one package.
JP 05317357 describes a method for making designs printed on the reinforcing sheet of paper diapers, such that the designs vary with the paper diapers. The method comprises providing a printing plate for printing the reinforcing sheet of paper diapers. The printing plate 9 is divided along its longitudinal direction per width S and different designs are printed on each division I-VIII so that the reinforcing sheet has different designs for each diaper.
US 2006/0009744 discloses decorative components of various sizes and uses for assembly into absorbent articles manufactured using a decorative component material. The absorbent articles have a variety of decorative appearances. A method for producing absorbent articles from the decorative component material comprises providing a roll of decorative component material comprising a design from which absorbent articles having a variety of desirable decorative appearances can be manufactured on a single assembly line. The roll of decorative component material may comprise one or more noncomprehensive designs that, upon assembly of a component made from the material into an absorbent article, provide a different decorative appearance to each successive article made in continuous assembly.
U.S. Pat. No. 6,558,499 discloses an absorbent article including one or more graphics thereon and a method for making the same, wherein the method comprises the step of attaching the cross-directional continuously moving discrete absorbent cores to the continuously moving appliqué layer such that a graphic corresponds to each of the cross-directional continuously moving discrete absorbent cores; cutting the continuously moving appliqué layer with the attached cross directional continuously moving absorbent cores at a predetermined position between said cross directional continuously moving absorbent cores to form discrete absorbent articles, wherein each absorbent article in the set of absorbent articles has an appliqué layer and the appliqué layer includes a graphic.
All the above-mentioned methods have the disadvantage of requiring complicated and expensive production lines having low flexibility or rolls having a large diameter, which may deteriorate the manufacturing speed and requires additional space for the production line.
Hence, there is a need for a method that can provide a large number of different graphics imparted on absorbent articles, using an uncomplicated and inexpensive equipment.